EP 0642068 B1 19981021 - Pilot operated hydraulic valve
Title (en)
Pilot operated hydraulic valve
Title (de)
Vorgesteuertes Hydraulikventil
Title (fr)
Vanne hydraulique servocommandée
Publication
Application
Priority
DE 4330073 A 19930906
Abstract (en)
[origin: EP0642068A2] Generic type of the invention: pilot-controlled hydraulic valve for changing over the valve input pressure (p1) between a working pressure value and a lower circulating pressure value, in particular a pressure limiting valve. A main flow path is provided here with inlet (16) and outlet (17), a main valve (HV) arranged in the main flow path and a pilot control valve (VV1) operatively connected to the main valve. The main valve (HV) is provided with a resiliently elastic reset element (6). Object of the invention: production of a valve of the abovementioned type which is distinguished by a low circulating pressure with nonetheless high operational reliability, even for relatively high working pressures and relatively large flows. Achieving the object: in conjunction with the features of the generic type, provision is made of a relieving device (EV) which can be activated by the pilot control valve (VV1), is operatively connected to the reset element (6) and controls the resetting effect on the main valve (HV). Furthermore, the relieving device (EV) is designed such that it can be changed over, under the effect of the pilot control valve (VV1), between an activated position with a reduced effect of the reset element (6) on the main valve (HV) and a deactivated position with increased effect of the reset element on the main valve. <IMAGE>
IPC 1-7
G05D 16/20; G05D 16/16; G05D 16/10; G05D 16/04; F16K 31/40; F15B 13/042; F15B 13/043
IPC 8 full level
F15B 13/042 (2006.01); F15B 13/043 (2006.01); F16K 31/40 (2006.01); G05D 16/04 (2006.01); G05D 16/10 (2006.01); G05D 16/16 (2006.01); G05D 16/20 (2006.01)
CPC (source: EP US)
G05D 16/2097 (2018.12 - EP US); Y10T 137/777 (2015.04 - EP US)
Designated contracting state (EPC)
CH DE DK GB IT LI SE
DOCDB simple family (publication)
EP 0642068 A2 19950308; EP 0642068 A3 19961002; EP 0642068 B1 19981021; DE 4330073 A1 19950309; DE 59407117 D1 19981126; US 5564673 A 19961015
DOCDB simple family (application)
EP 94113923 A 19940905; DE 4330073 A 19930906; DE 59407117 T 19940905; US 30047194 A 19940902